> ## Documentation Index
> Fetch the complete documentation index at: https://docs.modulate.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Music Detection

> Music detection APIs — batch classification and real-time streaming over WebSocket.

Music detection classifies audio as music, speech, or neither, returning frame-level probabilities across the clip.

|              | Batch                          | Streaming                                     |
| ------------ | ------------------------------ | --------------------------------------------- |
| **Use case** | Classify a complete audio file | Real-time frame-by-frame classification       |
| **Protocol** | HTTP POST                      | WebSocket                                     |
| **Output**   | Full response after processing | Frames emitted progressively as audio arrives |
| **Latency**  | Proportional to file length    | \~192ms per frame                             |

For a side-by-side comparison with the other Modulate capabilities, see [Which API should I use?](/guides/which-api).

## Authentication

Batch uses the `X-API-Key` header. Streaming uses an `api_key` query parameter at connection time. See [Authentication and rate limits](/guides/authentication).